Hackers hit the Sony Corp.’s huge Playstation network this weekend, before a bomb threat was made against a flight carrying a top Sony executive in the U.S.

The tech company said on its Playstation blog Monday that the network was taken down by a denial of service attack, but added that none of the personal data of its 53 million users was compromised.

“We have seen no evidence of any intrusion to the network and no evidence of any unauthorized access to users’ personal information,” said the blog post by Sid Shuman, senior manager of social media.

Somebody with the Twitter handle @LizardSquad claimed responsibility for the data breach on Sunday, Reuters said. The purported hacker said the attack was carried out to warn the Japan-based firm that more profits needed to be spent on data security.

“Sony, yet another large company, but they aren’t spending the waves of cash they obtain on their customers’ [PlayStation Network] service. End the greed,” said one @LizardSquad post on Sunday.

In other unsubstantiated claims, the user said that Blizzard Entertainment, the maker of World of Warcraft, had been targeted and also threatened Microsoft’s Xbox Live network.

The posts took an alarming turn when @LizardSquad tweeted at American Airlines on Sunday, claiming to know that explosives were aboard a flight being taken by Sony Online Entertainment President John Smedley.

The San Diego-bound flight from Dallas was later diverted to Phoenix, and its passengers have since made their way to San Diego.

Reuters reports that American Airlines said in a tweet that it was “aware of threats” made over Twitter and had alerted security.

American Airlines spokeswoman Michelle Mohr told AP that she couldn’t discuss security matters and referred questions to the FBI. The FBI declined Reuters’ request for comment.